1. Field of Invention
This invention generally relates to electrostatic copiers, and more specifically to such copy machines having plural input optical scan stations for receiving images to be copied combined with a common developing and copy feed mechanism for making copies of the scanned images in a multiplexed fashion and selectively delivering the copies back to the correct station.
2. Prior Art
At the present time coin operated, manual feed electrostatic photocopy machines are commonly available in public libraries, governmental offices, and other public areas; as well as in private offices, for making one-at-a time copies of individual documents, pages of books, or the like. Such machines have only a single scanning station for receiving each document to be copied in sequence; and if more than one user wishes to employ the machine, such person is delayed and must await the completion of use by the prior user. In many libraries and other busy locations, more than one, and in some instances many, machines of this same kind are installed to reduce the waiting time for the availability of a copy machine. However, the use of multiple machines is often unsatisfactory and wasteful in both space and cost, since each machine occupies a considerable amount of space than could be otherwise used to advantage; and furthermore there is usually still insufficient machine capacity to fulfill the needs of a plurality of users wishing to use the machines at about the same time. Additionally, this practice is also wasteful in both equipment and cost since each machine comprises a completely self-contained unit including its own optical scanning mechanism, paper feed, electrostatic development, and copy delivery mechanisms; many of which mechanisms operate in a stop-go time sequence and therefore have insufficient operating time, from an efficiency standpoint, even when the overall machine is continuously in use.
More sophisticated high speed electrostatic copy machines are also presently available that include programmable automatic mechanisms for automatic feed and copying of series or stacks of documents at very high speed. In such machines, the documents to be copied are automatically fed to the machine in sequence and one, or many copies of each are very rapidly made and automatically collated and delivered by the machine. Similarly high speed, high capacity machines are also available for automatically copying images from strips of film, webs, magnetic tapes, and the like, wherein the carriers are automatically fed to the machines, the images are automatically copied, and the copies are automatically collated and delivered in a preprogrammed arrangement. However, such high speed automatic machines are far too expensive, and otherwise not useful or needed, for individual manually fed copy making by coin operated users, or by other users on a one-copy-at-a-time basis, since the high speed of operation of the reproducing mechanism is of little benefit to the user in view of the comparatively long time period required to manually feed the documents or books to be copied to the scanner in a one-at-a-time manner.